Russian baritone (b. 1834; d. 1905), born Gennady Petrovich Kondratyev (Геннадий Петрович Кондратьев).
As a youth Kondratyev was in the Aleksandrinsky Academy and the Pavlovsk Military School, where he sang in the chorus, learned to play the violin and cello, and conducted the in-house orchestra. He left military school in 1856, and went to Italy to train as a singer in Milan, later touring in Florence. He began his stage career in Tiflis in 1863, and made his debut in the Russian Opera in Saint Petersburg two years later in Glinka's Ruslan and Lyudmila. From 1872 until 1900 he was the chief director of the Imperial Theatres in Saint Petersburg, and in his capacity as director he oversaw the premiere of Tchaikovsky's opera The Queen of Spades at the Mariinsky Theatre in 1890.
Correspondence with Tchaikovsky
One letter from Tchaikovsky to Gennady Kondratyev has survived, dating from 1886, and has been translated into English on this website: